1. Field of the Invention
This invention relates generally to displays of information data in the form of sequential lines of symbols commonly comprising lists of words and numbers, and more specifically relates to the use and control of electronic forms of such displays.
2. Description of the Related Art
It has become well-known to display lists of words and numbers on electronic display screens for ready access by users. Often, such lists extend in length beyond the dimensions of the electronic screen, and in such cases it has further become well-known to cause the image of the list to xe2x80x9cscrollxe2x80x9d past the screen so that a line of text comprising words, numbers or other symbols, appears to travel from one edge of the screen to the other until a desired section of the list, or portion of a line, appears on the screen.
It is known that the systems and methods currently being used to control the scrolling motion of the screen image are subject to numerous limitations and disadvantages. For example, in one system a cursor may be positioned at one edge of the screen and then moved toward the opposite edge while holding down a selected xe2x80x9cmousexe2x80x9d button, thereby engaging and xe2x80x9cdraggingxe2x80x9d the screen image in a desired direction. It is well known that such displacement of the screen image is slow and cumbersome except for relatively slight relative movements. Another system in current use activates an automatic continuous xe2x80x9cscrollingxe2x80x9d motion of the image when the cursor is positioned on a specific portion of the image, while a selected mouse button is depressed. This requires holding down the selected button until the desired portion of the screen image is displayed. A related system in current use varies the speed of the scrolling motion in accordance with the position of the cursor relative to the edge of the screen. All of these cursor position-responsive control systems are subject to similar limitations of screen clutter, lack of aesthetic visual appeal, and the requirement for manipulation and handling of the mouse device.
The invention herein disclosed improves upon the scroll-like display of data on electronic display screens by making it possible for a user/viewer to access a desired portion of a long list of data and information by scrolling to the location of that portion rapidly and in a more natural manner than heretofore possible.
The present invention overcomes and avoids the limitations of known control systems for scrolling electronic displays by providing a touch-screen responsive system that imparts a scrolling motion to the displayed image in response to the motion of a finger in contact with the screen. The speed and direction of motion of the finger along the screen determines the initial speed and direction of motion for the image. After the finger separates from the screen, the image continues to move in the same direction at a gradually decreasing speed until motion is stopped manually by touching the screen without movement of the finger, or the speed decreases to zero, or to a predetermined minimum speed, or until the image reaches its xe2x80x9cendxe2x80x9d. Alternatively, continued motion of the image may be achieved or again increased by repeating the xe2x80x9csweeping motionxe2x80x9d of a the user""s finger along the screen. Motion of the displayed image may be stopped manually by applying a finger to the screen without moving it along the surface of the screen for a finite period of time. If a finger is applied to the surface of the screen for a shorter period of time, for example for a period less than a minimum set time, the finger touch can be deemed to be a xe2x80x9cselectionxe2x80x9d of an item or xe2x80x9cthingxe2x80x9d corresponding to the image displayed at the touched location. Still further, if the finger touch on the screen is made to move with the display, but at a slower rate than the then-current rate of movement, the display will be slowed to a rate corresponding to the motion of the finger at the movement that contact is broken.
This operation of the system of this invention is achieved by programming a microprocessor-based control system to displace the image on a screen display, such as the screen of a conventional cathode ray tube, in response to a finger touch on the screen and the direction of a finger motion along the surface of the screen at the initial speed of the finger motion. Thereafter, the speed of displacement is caused to decay at a selected rate (units of displacement per unit of time, or a function thereof), until the displacement finally stops (for example, due to having reached the end of the xe2x80x9cscrollxe2x80x9d) or until it is stopped deliberately as explained herein.
In accordance with this invention, the scrolling motion of data on the display screen moves in a seemingly xe2x80x9cnaturalxe2x80x9d way, moving initially at a speed imparted by the motion of the user""s finger, with the speed thereafter slowing at a constant rate until it ultimately comes to rest, unless it is terminated earlier.
Moreover, if the speed of scrolling is found to be slow at a point deemed to be too far before the desired location in the scroll, the scrolling speed may be increased as many times as possible by merely touching the screen again to impart xe2x80x9cnewxe2x80x9d motion to the display.
At any desired point or time while a scrolling motion is in progress, it may be stopped entirely, again in a seemingly xe2x80x9cnaturalxe2x80x9d way, by merely touching one""s finger to the screen while holding it substantially stationary for a predetermined period of time. The reason for requiring a predetermined time-period for stationary [i.e. no-motion] touch time is to assure that the timing mechanisms will have sufficient time to distinguish between a touch intended to stop the scrolling motion and a touch [shorter in time] intended to xe2x80x9cselectxe2x80x9d or xe2x80x9cmarkxe2x80x9d a particular item that is included in the scrolled data. xe2x80x9cTouch markingxe2x80x9d is a well-known feature of scrolled display technology at this time, but this invention discloses its use in combination with a new, and heretofore unknown, form of scrolling motion control.
These and other features and advantages of this invention will be made more apparent to those having skill in this art, by reference to the following specification considered in conjunction with the accompanying drawings, in which: